The 3RB1246-1PB01: The 1.25...6.3 A setting range matches small to medium motors on a 400 V line — think fractional-horsepower pumps, small fans, or conveyor drives. The trip class range (5 to 30) lets you tune the thermal memory: Class 5 for fast-acting protection on short-cycle loads, Class 30 for high-inertia starts that need a longer thermal curve without nuisance tripping. Ground fault signaling is built in, so the relay can report earth leakage without an external module. The manual-automatic-remote reset options give flexibility: manual for commissioning, automatic for unattended lines, remote for PLC-controlled reset sequences.
Integration Notes
The screw terminals on the auxiliary circuit accept standard ferruled wire; strip length and torque follow the Siemens SIRIUS wiring guidelines. The DC 24 V coil supply must be clean — verify the power supply can hold the relay in the reset state without dropout during line sags.